【摘要】 树脂传递模塑成型工艺(RTM)中剪切变形会导致织物预成型体几何形式发生改变，为研究剪切变形对织物预成型体的体积分数、渗透率及填充浸润的影响，针对低黏度液体设计并建立了恒流条件下径向流动实验测量系统，考察了一般各向异性织物发生剪切变形后主渗透率、主渗透率方向、各向异性度及浸润特性的影响规律。结果表明：恒定流量下，随着剪切角的增加，主渗透率值逐渐减小，织物的渗透率各向异性度逐渐增加，主渗透率方向与x轴夹角逐渐减小；不同剪切角度对入口压力及填充浸润时间具有一定影响，剪切角越大，填充浸润时入口压力越大，织物完全浸润所需的时间越长；数值模拟可准确预测充模过程中的浸润特性。更多还原

【Abstract】 Objective Based on the resin transfer molding process, Shear deformation will change the fabric structure, which directly reduced the fiber bundle spacing and porosity and affected the permeability and main permeability direction of the fabric. In order to ascertain the governing principles. the effect of shear deformation on the principal permeability component of anisotropic fiber fabrics, permeability anisotropy, principal permeability direction, inlet pressure, and the time required for filling and infiltration is investigated to lay the foun-dation for practical applications and verified with numerical simulations.Method An experimental measurement system for the radial flow of a low-viscosity liquid（corn oil） under constant flow conditions was designed and set up using a plain glass woven fabric（fabric face density of 0.482 kg/m² and glass fibric density of 2 500 kg/m³. The warp and weft yarn density was 1 105 tex, while the warp density was 30 pieces/（10 cm） and the weft density was 22 pieces/（10 cm）） with rectangular pores. The principal permeability component was obtained using the permeability formula for anisotropic fabrics and the inlet pressure change was recorded by the pressure transducer in the process of filling and infiltration.Result As the shear angle was increased from 0° to 30°, the internal porosity of the fabric was decreased and the fiber volume fraction was increased. At shear angles between 10°-20°, the fiber volume fractions obtained from the theoretical equations were basically the same as the experimental values; while at the shear angle of 30°, the theoretically predicted fiber volume fraction was about 0.8% higher than the experimentally tested value. With the increase of the shear angle, the magnitude of the principal permeability K₁ and K₂ showed a significant decreasing trend, in which K₁ decreased from 20.20 × 10^-10 m² to 11.44 × 10^-10 m² and K₂ from 16.1 × 10^-10 m² to 6.31 × 10^-10 m², the degree of anisotropy of the fiber fabric increased by 1.6% and 12.0%, and the anisotropy of the fabric was increased by 1.6%, 12.0%, and 44.8%. The direction angle of the principal permeability was decreased by about 29°, 39°, and 46°. At shear angles of 0°, 10°, 20°, and 30°, the time required for the elliptical flow front to fill and infiltrate along the long axis is 39.0, 37.0, 36.0, and 32.0 s, respectively, and the time required for the fabric to be completely filled and infiltrated is 45.0, 48.0, 49.0, and 54.0 s, with the maximum values of the inlet pressures being 23.2, 30.0, 33.0, and 38.9 kPa, respectively. Comparing the different inlet pressure curves, the length of the long and short axes of the flow front, and the contour of the flow front obtained from the experimental and numerical simulations were in excellent agreement, and the time error of long axis full infiltration was 4.0%. the total wetting time error was 2.4%, the maximum inlet pressure error was 7.9%. The numerical simulation could accurately predict the change of inlet pressure during the filling and wetting process, and this method could be used to study the wetting characteristics of different fabrics after shear deformation.Conclusion In radial flow experiments, an increased fiber volume fraction leads to a reduction in the principal permeability（K₁, K₂） of the fabric and alters both the anisotropy degree（K₁/K₂） and the orientation of the primary permeability. The fitting formula obtained from the experiments effectively predicts the direction of the principal permeability of the fabric after shear deformation, providing a solid foundation for subsequent investigations into changes in the directional principal permeability of the fabric. The augmentation of fiber volume fraction results in an elevation of inlet pressure and an increase in the time required for complete filling and infiltration of the fiber fabric during the liquid filling process, making the filling process more challenging. Numerical simulations offer a more economi-cally and conveniently prediction of the liquid filling and infiltration process in fiber fabrics. Subsequently, numerical simulations can serve as a basis for studying the wetting characteristics of different fiber fabrics.更多还原